Cold water curable orthopedic cast

Abstract

A bandage material for forming in place an orthopedic cast comprising a pliant, large mesh fabric carrier formed from a knit of a high-strength, high-modulus fiberglass yarn with a low moisture pick-up, the fabric carrier having openings of relatively large transverse dimension, and being coated with a polymer composition comprising a cold water curable polyurethane prepolymer comprising the reaction product of a polyalkylene ether diol, a polyalkylene ether triol and a diisocyanate.

What is claimed as new and desired to be secured by Letters Patent of the United States is: 
     
       1. A bandage material for forming in place an orthopedic cast comprising a pliant, large mesh fabric carrier formed from a knot of a high-strength, high-modulus fiberglass yarn with a low moisture pick-up, the fabric carrier having openings of relatively large transverse dimension, and being coated with a polymer composition comprising (a) a water curable polyurethane prepolymer comprising the reaction product of a polyalkylene ether diol, a polyalkylene ether triol and a diisocyanate, wherein the ratio of diol to triol is from 1:9 to 9:1 and (b) an amine catalyst. 
     
     
       2. The bandage material according to claim 1, wherein the polymer composition further comprises a mineral acid. 
     
     
       3. The bandage material according to claim 2, wherein the mineral acid is phosphoric acid. 
     
     
       4. The bandage material according to claim 1, wherein the amine catalyst is a tertiary amine. 
     
     
       5. The bandage material according to claim 4, wherein the tertiary amine is [(CH 3 ) 2  NCHCH 2  ] 2  O. 
     
     
       6. The bandage material ccording to claim 1, wherein one equivalent of polyol (diol and triol) is reacted with more than 1.8 equivalents of isocyanate. 
     
     
       7. The bandage material ccording to claim 1, wherein the polyurethane prepolymer comprises the reaction product of polypropylene ether diol, polypropylene ether triol and a diisocyanate. 
     
     
       8. The bandage material according to claim 7, wherein the diisocyanate is a modified diisocyanate prepared by reacting a diisocyanate with less than a stoichiometric amount of carbodiimide. 
     
     
       9. The bandage material according to claim 8, wherein the modified diisocyanate is a mixture of OCN--R--NCO, and ##STR6## where R is ##STR7##